Cable cutter



De 12, 1961 H. H. TOWNSHEND, JR 3,012,321

CABLE CUTTER 2 Sheets-Sheet 1 Filed June 1, 1960 INVENTOR Henry H. v Townshend, Jr.

ATTORNEYS 1951 H. H. TOWNSHEND, JR 3,012,321

CABLE CUTTER 2 sheets-sheet 2 Henry H. 75wnshend,JI

Filed June 1, 1960 A OR EY United States Patent 3,012,321 CABLE CUTTER Henry H. Townshend, In, New Haven, Conn., assignor to J. T. Henry Manufacturing Co., Inc, Hamden, Conn., a corporation of Connecticut Filed June 1, 1960, Ser. No. 33,205 4 Claims. (Ci. 30-131) This invention relates to cable cutters, and relates more particularly to cable cutters of the type which, while not limited thereto, are especially useful for cutting stranded cable. Stranded cable is often formed of a plurality of relativelysoft strands forming the outer part of the cable and disposed around a relatively hard strand forming the core of the cable and providing a strengthening member. The relatively soft strands may be formed of aluminum, for example, and the core strand may be formed of steel.

Heretofore, difficulty has been encountered in cutting such a stranded cable with thin-edged cutters of the type usually employed to cut a plurality of relatively soft strands. The blades of such light cable cutters often fail to shear the hard core strand of the cable, and usually the blades are nicked by this strand. Furthermore, as closing movement of the blades is resisted by the core strand, the blades tend to twist relatively to one another in a plane substantially at right angles to the swinging axis ofthe blades. This results in lateral separation of the cutting edges and impairs the shearing efiiciency of the cutter;

One object of the invention is to provide an improved cable cutter which is particularly well adapted for cutting stranded cable such as described above.

Another object is to provide a cutter having an improved blade construction.

Another object is to provide a cable cutter having improved means for holding a cable during a cutting operation to resist twisting movement of the cable and thereby inhibit twisting movement of the blades.

The improved cable cutter may be of the type which is manually operated, as by conventional handle members. However, in the preferred form the cable cutter is power operated and the last-mentioned form is illustrated in the accompanying drawings.

In the drawings:

FIG. 1 is a fragmentary top plan view of a cable cutter embodying the invention;

FIG. 2 is a fragmentary side elevational view of the cutter;

FIG. 3 is a fiont elevational view of the cutter;

FIG. 4 is a sectional view taken on line 4 4 of FIG. 1;

FIG. 5 is a diagrammatic view illustrating one of the first stages of a cutting operation; r

FIGS. 6, 7 and 8 are views similar to FIG. 5 and illustrate progressive stages of a cutting operation;

FIG. 9 is a fragmentary perspective view of one of the cutter blades; and

FIG. 10 is a view similar to FIG. 4 and further illustrates the cooperation of the cable-holding means with a cable which is to be cut.

In the drawings, the blades of the cutter, which may be of identical form, are indicated generally at 10. The blades are shown in association with blade-operating links or levers 11 pivoted to an actuating rod 12 operating within a tubular member 13 and driven from a fluid cylinder, not shown. The tubular member 13 is provided with a bifurcated extension 14 at its outer end, and within which the blades extend in lapping relation to one another, the blades being pivoted by a bolt 15 extending through the blades and the extension 14, as shown in FIG. 2. Each blade 10 has a shank portion to which one end of one link 11 is pivoted as at 16. The other ends of the links are pivoted to the actuating rod 12 by a pivot 17 providrespective arms.

ing a common pivotal axis for the links 11. The tubular member 13 is provided with diametrically opposite slots 1?) through which the respective links 11 extend. It will be understood from the foregoing that when the actuating rod 12 is extended outwardly in the tubular member 13, the blades 10 are moved toward their closed positions through the action of the links 11. The blades are opened when the actuating rod 12 is retracted.

The cable-holding means of the cable cutter is indicated generally at 18, and include a metal member 19 which is generally of inverted U shape in cross section. The member 19 at the distal end portions of the arms thereof is provided with plate-like parts 20 through which the bolt 15 extends to support the member 19 on the extension 14 of the tubular member in straddling relation to the blades. To prevent angular movement of the cable-holding member 19 on the tubular member 13, a pin 21 may extend through the arms of the member 19 and through the extension 14 of the tubular member, the pin 21 being spaced from the bolt 15, as indicated in FIG. 2. The cableholding member 19, which supports the cable at both sides of the point at which it is to be cut, that is, on each side of the cable cutter, provides clearance for the swinging blades of the cutter. and tends to hold the cable stationary in a position between the blades as the blades swing toward the cableto cut it.

To hold the cable in the aforesaid manner, the cableholding member 19is slotted transversely thereof, the slot being indicated generally at 22. This slot extends through the portion of the member 19 which interconnects the arms of the last-mentioned member, and the slot also extends through the arms, the slot extending toward the distal end portions of the arms and forming a tortuous cable path in each of the arms. The portion of each cable path which extends generally outwardly in the corresponding arm is indicated at 23. As viewed in FIG. 1, one path portion 23, that is, the near one, is inclined somewhat to the left, while the other, the far one, is inclined somewhat to the right. The path portion 23 in the near arm terminates in a path extension 24 projecting to the right, while the path portion 23 in the other arm terminates in an extension 24 projecting to the left, the arrangement being such that the path extensions 24 in the arms of the cable- ,holding member 19 approach alignment with one another so that a cable, such as that shown in broken lines in FIG. 4, may extend through the path extensions without being bent.

The purpose of the aforementioned path extensions is to hold a cable captive when and as the blades of the cutter approach the cable to cut it, that is, to prevent movementof the cable outwardly between the blades during the first stage of a cutting operation. The cableholding member 19 serves the additional purpose of inhibiting twisting of the cable on an axis generally at right angles tothe swinging axis of the blades as the blades bite or cut into the cable to sever it. The path extensions 24 terminate in arcuately formed edges 25 of the respective arms, which form cable seats to partially overlie a cable in the manner indicated in FIG. 1. These cable-seating portions of the arms may be reinforced as by generally C-shaped parts 26 fixed to the The C-shaped parts may slightly overlap the slot 22, as shown in FIG. 1. When a cable of the size approximating that shown in broken lines in FIG. 4 is inserted in the cable holder, it is necessary to bend the cable to move it through the tortuous cable path 22 in order to seat it in position to be cut.

The blades of the cable cutter have concave cutting edges 27. In the illustrated form, the cutting edge 27 of each blade has portions thereof formed on radii of different lengths in a manner similar to that shown and described in my US. Patent No. 2,870,538, issued January 27, 1959. This, however, is not essential, The blades of the cutter are provided with extensions 28 similar to those shown and described in the last-mentioned patent. Each blade extension 28 cooperates with the other blade to resist blade torque during a cutting operation, that is, twisting movement on an axis approximately at right angles to the pivotal axis of the blades. As shown in the drawings, each of the cutter blades is provided with a projection 29 extending beyond the wiresponding cutting edge 27. These projections (FIG. 1) extend toward one another. The projections form the blade tips and the construction is such that, when and as the blades move from their open positions toward their. closed positions, the blade tips overlap (FIG. 5) before or as the blades commence knifing into the cable to shear it. When the blades of the cutter have reached their positions shown in FIG. 5, and then continue toward their closed positions, the cutting edges 27 of the blades define therebetween an opening which approaches an ellipse in outline but is not a true ellipse due to the fact that the outline of the opening has sharp ends instead of rounded ones. The outline of the opening between the blades may be more accurately described as having the appearance of an axial section of a double-ended conoid.

The cutting edges 27 of the blades are generally sharp and thin, as. indicated in FIG. 9, for optimum shearing action. To achieve this, the margins of the cutting edges are gently tapered. However, these tapered edges are interrupted by notches 30, one notch being formed in each blade. The notches 30 are provided to receive and shear the relatively hard center strand of the cable, and hence they are aligned with one another. To tend to insure that the center strand passes into the notches 30 as the blades close, the notches are aligned with one another at the widest point of the aforementioned axial section of the double-ended conoid. It will be understood from the foregoing that the form of the opening between the blades (FIGS; 5 and 6) is such as to tendto center the cable, whether relatively large or small, in the center of the opening, so that the center or core strand of the cable is maintained in alignment with the notches 30 which close upon it. The bottoms of the notches 30 are rounded and do not present any thin cutting edges to be nicked by, the relatively hard center strand of the cable, and the notches may be of a width just slightly in excess of the diameter of the largest anticipated center strand, say of an inch, for example. The depth of each notch 30 may be just slightly in excess of the radius of the largest anticipated core strand. As indicated above, the action of the cutting blades during, a cutting operation is illustratedin FIGS. 5 through 8. In FIG. 5, the cable is shown centered in the opening between the blades as the blades close and the blade'tips overlap. The cable holder 18 also serves to center'the cable and hold it in proper relation to the notches 30. The arcuate seats of the holder 18 also tend to maintain the cable.

portions of the blades, that is, by the cutting surfacesv interrupted by the notches 30.

The outer strands of the cable may also be cut .by the. notched blade portions where these portions come in contact with the cable as the blades move to their closed positions; As indicated FIG. 6, the opening between the cutting edges of the. blades is narrowed and reduced in length as the blades move toward their closed positions, and also, as shown in the last-mentioned view, the blades tend to first cut the strands of the cable which are at each side of the full lines in FIG. 10 also must extend through the cable cutter at an angle of less than 90 to the plane of the longitudinal axis of the cable cutter. the center or core strand of the cable received in the opening formed between the two notches 30, and about to be cut, all of the other strands of the cable having been previously severed; FIG. 8 illustrates the positions of the cutting blades after the center and relatively hard strand of the cable has been cut. In these positions the cutting edge of each blade is fully overlapped with the other blade.

It will be understood from the foregoing that during a cutting operation the cable interposed between the cutting edges of the blades is held by the cable-holding means in a manner to inhibit twisting of the cable on an axis substantially at right angles to the pivotal axis of the blades in a manner to reduce bladetorque. Hence, the cutter has a bettershearing action. As indicated in FIG. 10, the cable holding means may effectively hold cables of a relatively wide range of diameter. The'cable shown in full lines in FIG. '10 has a larger diameter than the cable shown in brokenlines in FIG. 4, while the cable shown in broken lines in FIG. 10 is of smaller diameter than the cable shown in FIG. 4. The cable shown in'FIG. 4 extends through the cutter at substantially right angles to the plane of the cutting blades. However, the smaller cable shown in broken lines'in FIG. 10, to be fully seated in the cable-holding means, must extend through the cutter at a somewhat smaller angle to the plane of the blades. The larger cable shown in cutting blades. However, the lastmentioned cable, to be fully seated in the cable-holding means, is inclined in a direction opposite to the inclination of the smaller cable shown in broken lines inthe last-mentioned view. In all instances the cable is held in engagement with the arcuate seats 24 of the cable-holding means at opposite sides of the point at which the cable 'is to be sheared, and is maintained at an angle approaching 90 to the plane of the blades. I

It will be understood from the foregoing disclosure that a cable. cutter is provided which is particularly well adapted for cutting stranded cable of the type consisting of relatively soft outer strands and a relatively hard center or core strand. It will be manifest that the cable cutter includes improved cable-holding means to facilitate the shearing action of the cutter blades and it will be evident thatthe cable cutter includes an improved blade construction. v

While onlyfone form of the cable cutter has been illustrated in the drawings and described above, it will be evident to those versed in the art that the cable cutter may take other forms and is susceptible of 'various changes in details Without departing from the principles I of the invention and the scope of the appended claims.

What I claim is:

1. In a cable cutter for cutting a 'cable comprising relatively soft outer strands and a relatively hard core strand, a pair of swingabl'e blades supported in pivotal relation to one another and provided with operating members, the blades having means thereon providing cutting edges whicnas the'bla'd'es: close, define between the blades an opening having substantially the outline of an axial section of a double-ended conoid, said cutting edges having continuous thin sharp portions for cutting the outer strands of the cable, said edge portions being interrupted by thick notched cutting edge portions to cut the core strand of the cable, the last-named portions being'disposed on the respective blades at substantially the Widest point of the double-ended conoid, and cable-holding means tending to center a cable in said opening and including a cable-holding member. generally of inverted U shape in cross section and embracing the blades in fixed relation to their swinging axes, said member having a substantially transverse slot formed therein providing cable seats at opposite sides of the FIG. 7 shows point at which the cable is to be cut and providing a tortuous cable path leading to said seats.

2. A cable cutter as defined in claim 1 wherein said cable seats are arcuately formed and partially overlie the cable to prevent it from slipping outwardly between the blades, one of said seats being disposed at one side of the cable axis and the other being disposed at the opposite side of the last-named axis, said seats being provided on the respective arms of the inverted U-shaped member.

3. A cable cutter comprising a pair of swingable blades supported in pivotal relation to one another and provided with operating members, and a cable holder for holding a cable between the blades during a cutting operation and comprising a member of inverted U shape in cross section and embracing the blades in fixed relation to their swinging axes, said member having a substantially transverse slot formed therein providing cable seats in the respective arms of the member and providing a tortuous cable path leading to said seats, the cable seats being arcuately formed and partially overlying the cable to prevent it from slipping outwardly between the blades, one of said seats being disposed at one side of the cable axis and the other being disposed at the opposite side of the last-named axis.

4. A cable cutter comprising a pair of swingable blades supported in pivotal relation to one another and provided with operating members, and a cable holder for holding a cable between the blades during a cutting operation and comprising a member of inverted U shape in cross section and embracing the blades in fixed relation to their swinging axes, said member having a substantially transverse slot formed therein providing a cable path extending through the portion of the member interconnecting the arms thereof and extending also generally outwardly in the arms to form cable path portions, said cable path portions in the arms being inclined in opposite directions from one another, the slot providing generally lateral cable path extensions at the outer terminals of said path portions, the path extension in one arm being arranged in opposing relation to the path extension in the other arm, said extensions forming cable seats at opposite sides of the axis of a cable extending through the holder, and the slot forming a tortuous cable path leading to said seats, the cable seats being arcuately formed and partially overlying the cable to prevent it from slipping outwardly between the blades.

References Cited in the file of this patent UNITED STATES PATENTS 489,612 Nagley Jan. 10, 1893 886,555 Tuttle May 5, 1908 1,890,355 Bailey Dec. 6, 1932 2,794,250 Bethune June 4, 1957 2,863,214 Szappanyos Dec. 9, 1958 2,870,538 Townshend Jan. 27, 1959 2,930,122 Pfundt Mar. 29, 1960 FOREIGN PATENTS 192,902 Germany Dec. 19, 1907 270,135 Great Britain May 5, 1927 

